"Everything I touched," Skinner said, "suggested new and promising things to do."

Building on the conditioned response research of Ivan Pavlov and John B. Watson, Skinner redefined psychology. His research examined relationships between an animal's response to the stimili of its environment. He further theorized that humans could learn to succeed with positive reinforcement.

He said, "The consequences of behavior determine the probability that the behavior will occur again."

His conditioning method led to the invention of the Skinner Black Box, a sound-proof container to observe and measure behavior. In working with rats and birds, Skinner believed that rewarded humans were predictable and could be trained to build a better world.

He carried this idea further in the controversial novel Walden Two (1948), exploring a utopia where behavior was controlled by technology. He wrote, "In Walden Two we have a different objective. We make every man a brave man. They all come over the barriers. Some require more preparation than others, but they all come over."

In an upbeat book called Enjoy Old Age: A Practical Guide (1983), Skinner wrote: "Old age is rather like another country. You will enjoy it more if you have prepared yourself before you go."